{"instruction": "You are an expert in named entity recognition. Please extract entities that match the schema definition from the input. Return an empty list if the entity type does not exist. Please respond in the format of a JSON string.", "schema": ["Chemical"], "input": "Separation was by a reversed - phase Chiralcel OD - RH column , under isocratic conditions using a mixture of acetonitrile - 2 mM ammonium acetate in water ( 60 / 40 , v / v ) as the mobile phase at a flow rate of 0 . 4 mL / min ."}
{"Chemical": ["acetonitrile", "ammonium acetate"]}